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jonny [76]
3 years ago
8

Can anyone help me with this last question?

Physics
1 answer:
Digiron [165]3 years ago
6 0

Answer:

v = 39.6 m/s (first answer option)

Explanation:

Use conservation of mechanical energy.

The starting is completely potential energy and the final is all kinetic energy:

m*g*h=\frac{1}{2}*m*v^2\\g *  h=\frac{1}{2} v^2\\9.8*80=\frac{1}{2} v^2\\v^2=1568\\v\approx 39.6\,\,m/s

which agrees with the first answer shown.

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